According to the sampling analysis of the straight hairline defects on the edge of Q355B hot-rolled steel,it was determined through the microscopic examination of electron microscope and combined with the field technology that the cause of the straight hairline formation was the folding defects formed when the corner of the casting blank was turned over to the table above during the width reduction rolling.The distance from the edge was 8～30 mm and the depth was 80～300 μm.According to the causes of defects,the corresponding control measures are made,and the straight hairline on the edge of the steel coil is well controlled.
维普
万方数据
